Lanius was the only son of Mergus of Avornis. Because Mergus had no male heirs, and went to great lengths to ensure his son was his successor, Lanius' eventual ascent to the throne was difficult, as he was displaced by his uncle, Scolpax for a time, then kept under the tight control of his mother, Certhia, before finally being forced to share the monarchy with a soldier named Grus.

Lanius' mother, Certhia, was the concubine of King Mergus. At the time of Lanius' conception, Mergus had sat upon the Diamond Throne for almost thirty years. He had already married his allotted six wives, and had no sons. [1] Thus, when Certhia, informed Mergus she was pregnant, Mergus was willing to violate the traditions of Avornis to secure a son as his heir, promising to make Certhia his queen.[2] However, he needed to first confirm that Certhia was carrying a son. Fearing that court wizards would not be able to keep quiet, he arranged to take Certhia to an unused area in the royal palace to meet a witch who called herself Rissa. Rissa confirmed that Certhia was carrying a boy. No sooner had she pronounce this, Rissa was taken over by the Banished One, who attempted to curse the unborn child. When Rissa came back to herself, she promised to make sure the taint of the possession would be taken away. She also suggested that if the Banished One hated and cursed the unborn son, he also feared him.[3]

Nine months later, Certhia gave birth to their son, whom Mergus promptly named Lanius. He married Certhia within minutes of Lanius' birth, making her queen. Lanius himself was rather small and scrawny.[4]